The invention relates to solutions, solid and liquid dispersions, and emulsions of biologically active organic compounds, in particular, herbicides and safeners, insecticides, fungicides, acaricides, nematicides, pheromones and repellents, and more particularly, insecticidal active substances.
Formulations of herbicidal, fungicidal or insecticidal active substances typically employ adjuvants, such as solvents, inert fillers, such as chalk, kaolin or silica, in particular surface-active substances. These formulations enable the preparations to wet substrates well and/or allow easy dispersion in water when they are used. In the case of the water-dispersible granules, adjuvants allow rapid disintegration after introduction into water.
There are processing and application problems associated with the preparation of formulated bio-active compounds, especially those having a relatively low melting point of 100xc2x0 C. and below. The prior art suggests a variety of solvents used in conjunction with these substances. Suitable suggested solvents are the high-boiling alkylbenzenes and xylenes, 1- or 2-methylnaphthalene, dimethylnaphthalenes, and other polynuclear aromatic compounds. Other water-immiscible solvents suggested include paraffin oils, vegetable oils, alicyclic compounds, alkanols, such as cyclohexanol and isooctyl alcohol, ethers, ketones, such as cyclohexanone, 4-methylcyclohexanone and isophorone, and esters, such as ethyl benzoate and tri-n-butyl phosphate. Many of these solvents have a low flash point temperature and are bioaccumulative, presenting hazards and toxicity problems.
Surprisingly, a class of organic solvent has been found to be highly effective for dissolving organic bio- active compounds, which has generally a high flash point, and is not bioaccumulative. The invention provides a solvent for formulated bio-active compounds that bio-degrades into non-hazardous, and is non-bioaccumulative.
The invention therefore relates to bio-active preparations, as solutions, solid or liquid dispersions, suspensions and emulsions comprising a bio-active compound and a water soluble or oil soluble acetal. Particular exemplary embodiments include emulsifiable concentrates (EC), water dispersible granules (WG), and suspoemulsions.
An further object of the present invention is to provide oil-in-water (O/W) emulsions of bio-active compounds and acetal in the oil phase, in stable colloidal dispersion in water.
Another object of the present invention is to provide formulated bio-active compounds characterized as having low volatility, high flash point and which are toxicologically safe.
Broadly, the bio-actives in solution, dispersion, emulsion or adsorption onto solids, together with acetals according to the present invention are active organic compounds, in particular, herbicides and safeners, insecticides, fungicides, acaricides, nematicides, pheromones and repellents.
The active substances, can be supplied in the form of liquid or solid formulations, containing bioactive substance content as a rule at from 1 to 80% by weight, preferably 5 to 60% by weight. The biologically active organic compounds mixed with acetal according to the invention, preferably include herbicides and safeners, insecticides, fungicides, acaricides, nematicides, pheromones and repellents, in particular bio-active substances, include glufosinate-ammonium, glyphosate, bialaphos; active substances from the phenoxy series, such as CMPP, MCPA, 2,4-D, active substances from the phenoxyphenoxy series, such as diclofopmethyl, or the heteroaryloxyphenoxy series, such as fenoxaprop-ethyl, fenoxaprop-P-ethyl; active substances from the urea series, such as isoproturon, diuron, linuron, monolinuron and chlortoluron, active substances from the series comprising the sulfonylureas, such as amidosulfuron, tribenuron (DPX-L5300), thiameturon-methyl (DPX-M6316), metsulfuron-methyl (DPX-T6376), primisulfuron-methyl and nicosulfuron; active substances from the series comprising the triazines, such as atrazine or simazine, active substances from the series comprising the imidazolinones, such as Imazapyr, Imazaquin, Imazethapyr and Imazamethabenz, and diphenyl ether derivatives, for example Acifluorfen, Fluoroglycofen, Lactofen and Bifenox, dicotylene herbicides, for example Ioxynil, Bromoxynil, Dicamba, Diflufenican, Fluroxypyr, Phenmedipham, Desmedipham, Bentazone, Metamitron, Metribuzin, Chloridazon, Ethofumesate or the active substance Trifluralin; and safenets, such as, for example, the compounds described in EP-A-86750, EP-A-94349, EP-A-191736, EP-A-346620, EP-A-333131, EP-A-269806, EP-A-159290, DE-A-2546845, PCT/EP-90/02020 and PCT/EP-90/01966; fungicidal active substances, such as, for example, active substances from the series comprising the azoles, for example Triadimefon, Cyproconazole, Myclobutanil and Dichlobutrazol; active substances from the series comprising the dithiocarbamates, such as Maneb, Zineb and Mancozeb, the benzimidazoles, for example Carbendazime, or active substances such as, for example, Procymidone, Iprodione, Vinchlozoline, Thiophanate-methyl, Cymoxanil, Folpet, copper oxychloride, sulfur or TPTH.
Pesticides used herein include, as non-limiting examples, active substances from the following chemistries: Avermectin, chloroacetanilide, azole, benzonitrile, phenoxies, imidazolinone, nitroaniline, pyrrole, organophosphorous, sulfonylurea, and benzimidazole.
Active substances are known and are described in xe2x80x9cPesticide Manualxe2x80x9d (by the British Crop Protection Council) or in xe2x80x9cFarm Chemicals Handbook 91xe2x80x9d (Meister Publishing Company, Willoughby, Ohio), both of which are hereby incorporated by reference.
Specific examples of pesticidal substances used in conjunction with the acetal solvent according to the invention are particulary those with melting points below about 100xc2x0 C., and there may be mentioned by way of examples, Phosalone, The Aclonifenoxadiazon mixture, Aclonifen-Linuron, Aclonifen-Bifenox, Bifenox, Acephate, Aclonifen, Alachlor, Aldicarb, Amethryn, Aminocarb, Amitraz, Azamethiphos, Azinphos-Ethyl, Azinphos-Methyl, Aziprotryne, Benolaxyl, Benfluralin, Bensulide, Bensultap, Benzoximate, Benzoylprop-Ethyl, Bifenthrin, Binopacryl, Bromophos, Bromo-Propylate, Bromoxynil Esters, Bupirimate, Buthiobate, Butocarboxim, Carboxin, Chlorbufam, Chlordimeform, Chlorfenson, Chlormephos, Chlorobenzilate, Fluorochloridone, Chloropropylate, Chlorphoxim, Chlorpropham, Chlorpyrifos, Chlorpyrifos-Methyl, Cloethocarb, Cyanophos, Cycloate, Cycloxydim, Cyfluthrin, Demethon-S-Methyl, Desmetryn, Dialifos, Diazinon, Diclofop, Dicofol, Diethatyl, Dimethachlor, Dimethomethryn, Dimethoate, Dinobuton, Dinoseb, Dioxabenzofos, DNOC (2-Methyl-4,6-Dinitrophenol), EPN (O-Ethyl O-(4-Nitrophenyl)-Phenylphosphonothioate), Etaconazole, Ethalfluralin, Ethiofencarb, Ethofumesate, Famphur, Fenamiphos, Fenitropan, Fenobucarb, Fenothiocarb, Fenoxaprop, Fenoxycarb, Fenpropathrin, Fenson, Flanuprop, Fluchloralin, Fluorodifen, Fluoroglycofen, Flurecol, Fluroxyupyr, Formothion, Furolaxyl, Furmecyclox, Haloxyfop, Heptenophos, Hymexazol, Iodofenphos, Ioxynil Esters, Isoprothiolane, Linuron, Metalaxyl, Metazachlor, Methamidophos, Methidathion, Methopotryne, Metolcarb, Monalide, Monocrotophos, Monolinuron, Myclobutanil, Napropamide, Nitrapyrin, Nitrofen, Nitrothalisopropyl, Oxabentrinil, Oxadiazon, Oxyfluorfen, Parathion-Methyl, Penconazole, Pendimethalin, Pentanochlor, Phenthoate, Phosfolan, Phosmet, Piproctanil, Pirimicarb, Prochloraz, Profluralin, Promecarb, Prometon, Propachlor, Propamocarb, Propanil, Propetamphos, Propham, Propoxur, Propthoate, Pyrazophos, Pyridate, Quinalphos, Quizalofop, Resmethrin, Secbumeton, Simetryn, Tebutan, Tefluthrin, Temephos, Tetramethrin, Tetrasul, Thiofanox, Tolciofos-Methyl, Triadimefon, Trichlorfon, Tridiphane, Triflumizole, Trifluralin, And Xylylcarb.
Other pesticides with melting points below 100xc2x0 C. which can advantageously be used in the compositions of this invention include the various esters of the class of phenoxyalkanoic acids. These include for example:
2,4-D: (2,4-dichlorophenoxy) acetic acid esters;
2,4-DB: 4-(2,4-dichlorophenoxy) butyric acid esters;
2,4-DB: 2-(2,4-dichlorophenoxy) propionic acid esters and their optical isomers;
MCPA: (4-chloro-2-methylphenoxy) acetic acid esters;
MCPB: 4-(4-chloro-2-methylphenoxy) butyric acid esters; or
Mecoprop: 2-(4-chloro-2-methylphenoxy) propionic acid esters and their optical isomers.
In the formulation of lipophilic pesticidal compound as aqueous preparations or organic preparations, and in cases where high melting acetals are employed, co-solvent or diluent may be included therewith, especially if the selected acetal solvent has partial solubility in water. Within the scope of the present invention, the term xe2x80x9cco-solventxe2x80x9d, means a solvent other than acetal and may be a single other solvent or a mixture of several solvents other than acetal in combination with the acetal. Organic co-solvent usually is not needed, and if present, is used in a weight ratio of solvent(s):acetal of 1:10 to 10:1, or whatever amount of solvent to be used which suitably cooperates with the acetal to form a solution of lipophilic pesticidal substance, and partition in the organic and/or aqueous phase.
Acetals used in the present invention are conventionally made by the elimination of water from an aldehyde group containing- compound and hydroxy group- containing compound, esp. an aldehyde and alcohol, under acidic conditions. Acetals from monoaldehyde and a single mono-alcohol have the general structure of (I): 
The R group can be branched or unbranched, saturated or unsaturated and aliphatic or aromatic. Preferably, R is C1- to C20-aliphatic, more preferably C4-C12 aliphatic groups. The acetals can be made from a reaction in a stoichiometric amount of one ore more alcohols with the aldehyde or in a mole ratio greater than stoichiomretric 2:1, e.g.2.5 or even 3:1 to 5:1 moles of alcohol:aldehyde. A single alcohol and aldehyde can be used, or a mixture of different alcohols with a single aldehyde, or mixture of aldehydes with a single alcohol, or a mixture of both different alcohols and different aldehydes be used. Acetals used herein may have a total of 3 to 50 carbon atoms, but more practically from 5 to 30 carbon atoms. Preferred acetals have a boiling point of from 100xc2x0 C. to 300xc2x0 C. Acetals and raw materials for their preparation are disclosed in U.S. Pat. Nos. 2,796,423, 2,842,499, and 3,563,893 which are hereby incorporated by reference.
Included in the definition of the term xe2x80x9caldehydexe2x80x9d herein are divalent aldehydes (dialdehydes), especially those having 2 to 10 carbon atoms. Dialdehydes such as glyoxal, tartaric acid dialdehyde, succinic dialdehyde, maleic acid dialdehyde and fumaric acid dialdehyde are particularly suitable for preparing the acetals used according to the invention. Acetal derived from glyoxal and alcohol has the general 
structure:
Wherein Rxe2x80x2 has the meaning ascribed above.
Alcohol means mono- or poly-hydroxy compounds. Thus, alcohol can be monohydric or polyhydric (2 to 20xe2x80x94OH groups), an alkanolamine, an alkoxylated (EO and or PO) alcohol, or carboxylated, acylated, or etherified- mono or -polyols, and each Rxe2x80x2 independently of one another can contain from 1 to 24 carbon atoms, preferably 4 to 12 carbon atoms, unsubstituted or substituted with O, N or S-containing groups. Alcohols can have Rxe2x80x2 groups that are branched or unbranched, substituted or unsubstituted, saturated or unsaturated, cyclic or acyclic, and aliphatic or aromatic. Examples of mono-, di- and trihydric alcohols are methyl-, ethyl-, n-propyl-, n-butyl-, i-butyl-, sec-butyl-, trihydroxy propane, glycerol, trimethylol propane, amyl-, octyl-, ethylhexyl, decyl-, octadecyl- alcohol, to name but a few of the myriad mono- or polyols. Exemplary cyclic alcohols include tetrahydrofurfuryl alcohol, cyclohexanol, cycloheptanol, cyclooctanol, 2-methylcycloheptanol, 3-butylcyclohexanol, and 3-methylcyclohexanol. Examples of ether alcohols are lower (C1-C10, i.e. methyl, ethyl, propyl, butyl, pentyl, hexyl, stc.) alkyl ethers of mono, di or tri ethylene or propylene glycol.
Oxygenated aldehyde, e.g. alkoxy substituted, or non-oxygenated aldehyde can be used.
Specific acetal embodiments for use in the presentation are: 
from butyraldehyde and 1,2,3-trihydroxy propane; and 
from butyraldehyde and 1,1,1-trimethylol propane; and 
from paraldehyde and 1,2,3-trihydroxy propane; and 
from paraldehyde and 1,1,1-trimethylol propane with a mole ratio of 0.33:1; and 
from isobutyraldehyde and 1,1,1-trimethylol propane reacted in a mole ratio of 1:1; for example.
Included within the meaning of acetals of the formula RCH(ORxe2x80x2)2, are ketals which have the formula R2C(ORxe2x80x2)2, wherein R2 is defined as for R above; and orthoesters which have the formula RC(ORxe2x80x2)3, wherein these R, and Rxe2x80x2 groups have the same meaning as above as for ketals and orthoesters such as linear, or branched alkyl and substituted and unsubstituted cycloalkyl. Exemplary R and Rxe2x80x2 groups are methyl, ethyl, n-propyl, n-butyl, i-butyl, sec-butyl, amyl, octyl, decyl, octadecyl, etc. When R is cycloalkyl, it may typically be cyclohexyl, cycloheptyl, cyclooctyl, 2-methylcycloheptyl, 3-butylcyclohexyl, 3-methylcyclohexyl, etc. R may be inertly substituted i.e. it may bear a non-reactive substituent such as alkyl, cycloalkyl, ether, halogen, etc. Typically inertly substituted R groups may include 3-chloropropyl, 2-ethoxyethyl, carboethoxymethyl, 4-methyl cyclohexyl, etc. The preferred R groups may be lower alkyl, i.e. C1-C10 alkyl, groups including e.g. methyl, ethyl, n-propyl, i-propyl, butyls, amyls, hexyls, octyls, decyls, etc. R and Rxe2x80x2 may preferably be butyl, isobutyl, 2-ethylhexyl in the case of ketal.
Exemplary oxygenated acetals used in the invention may be formed by reacting methoxyacetaldehyde with tetrahydrofurfuryl alcohol or with mono lower alkyl ethers of mono, di or tri ethylene or propylene glycols to form complex acetals.
Other exemplary complex acetals are:
methoxyacetaldehyde di(alkoxydiethoxyethyl) acetal,
methoxyacetaldehyde di(alkoxyethyl) acetal,
methoxyacetaldehyde di(alkoxyethoxyethyl),
methoxyacetaldehyde di(alkoxydiethoxyethyl) acetal.
Other complex acetals are formed by reacting methoxyacetaldehyde with mono alkyl ethers of mono, di or tri propylene glycols.
In forming the above described acetals from an aldehyde, conventional preparation methods can be used. Thus, each 1 mole of aldehyde is reacted with at least 2 mols, and preferably with a small stoichiometric excess of the particular alcohol or alcohol mixture. The reaction is carried out at elevated temperatures in the presence of a catalyst which may be an acid such as hydrochloric or p-toluene sulfonic acid or the catalyst may be boron trifluoride-ethyl ether complex as is known in the art. In general, the reaction temperatures may vary from about 190xc2x0 F. to about 250xc2x0 F. in order to form the acetal product at a reasonably rapid rate. The reactants may be dissolved in a suitable solvent, for example, benzene or other organic solvents, and both the solvent and the water formed during the course of the reaction, as the same evaporate from the reaction mixture, may be trapped and collected by a reflux condenser.
The proportion of acetal in the bioactive formulation can be up to 90% by weight, but in general from 10% to 75% by weight, and preferably 20% to 50% by weight and in particular 40% to 60% by weight acetal is contained in formulated embodiments.
In addition to the said active substances, and acetal, formulations usually employ surfactants, wetting agents, defoamers and also, optionally, further conventional formulating auxiliaries such as agglomeration auxiliaries, stabilizers and fillers. Specifically, the present formulations can optionally contain 2 to 60% by weight, preferably 5 to 50% by weight, of one or more wetting agents. Wetting agents, preferably are among the group of alkanesulfonates, alkylnaphthalenesulfonates, alkylbenzenesulfonates, alkylpolyglycol ether-sulfonates, alkylsulfosuccinic acid half-esters, fatty acid N-methyltaurides, fatty alcohol ethoxylates, ethylene oxide-propylene oxide block copolymers, or mixtures of the above wetting agents.
In addition to the said active substance, acetal and wetting agents, formulations can also contain antifoam compounds. Exemplary antifoams are described, for example, by H. -F. Fink and G. Koerner in technischen Chemie Ullmann""s Encyclopedia of Industrial Chemistry]xe2x80x9d, 4th revised and extended edition, Verlag Chemie, Weinheim, Volume 20, page 411-414, and by W. Schxc3x6nfeldt in xe2x80x9cGrenzflxc3xa4chenaktive Alkylenoxid-Addukte [Interface-active Alkylene Oxide Adducts]xe2x80x9d, Wissenschaftliche Verlagsgesellschaft MBM, Stuttgart 1973, pages 805-853, each of which are incorporated herein by reference. Solid antifoams, include for example, aluminum stearate. Liquid antifoams include perfluoroalkyl phosphinic-phosphononic acid .
Exemplary formulations of dissolved bio-active compound in acetal are, liquid oil-in-water (O/V) emulsions, liquid water-in-oil emulsions, emulsifiable concentrates (EC), suspoemulsions (SE), and water dispersible granules (WG), such forms as are recognized in the art.
In a solution formulation, the bio-active and acetal are directly mixed with or without co-solvent. Exemplary co-solvents are aromatic or aliphatic compounds, such as SOLVESSO 150, N-methyl pyrrolidone; methylated oils, such as methyl esters of soybean oil, cottonseed oil or rapeseed oil, or paraffin oils.
Emulsifiable concentrates (EC) are defined as a solution of bio-active in the acetal solvent in combination with one or more surfactants. Generally from 20 to 80% (by weight) of acetal, from 0.5 to 20% of bio-active compound and from 5 to 15% of surfactant are included in EC form.
Suspoemulsions (SE) are defined as a dispersion of solids and oil droplets dispersed in an aqueous continuous phase. The bio-active may be suspended as undissolved solid or dissolved in the oil phase, or dispersed phase oil phase and/or dissolved in or suspended in the aqueous phase.
Water dispersible granules (WG) are defined as a bio-active which is dissolved in acetal and adsorbed or absorbed with a solid carrier. Solid carriers known in the art include starches, clays, and silicas, including mixtures, and the like. WG""s can optionally contain wetting or dispersing agents, all of which are well known in the art. The WG is formed by making a solution of the bio-active in acetal, the solution is sprayed or mechanically mixed and pelletized or granulated in the conventional manner. Generally water dispersible granules comprise 0.5 to 50% of bio-active, 10% to 50% of acetal, 5% to 30% surfactant. The surfactants usable therewith are anionic, nonionic, zwitterionic, and cationic surfactants.
For formulated bio-activexe2x80x94acetal mixtures in the form of emulsions, it is preferred to choose an emulsifying system made up of anionic, nonionic, or cationic surfactants or mixtures of anionic and nonionic, or nonionic and cationic surfactants. Also, two nonionic surface-active agents can be employed, one having a more hydrophilic balance and the other a more lipophilic or hydrophobic balance. Particularly preferred amongst the hydrophobic surfactants are those which have a low HLB (hydrophilic-lipophilic-balance) and can act to prevent or inhibit crystal growth of a lipophilic bio-active ingredient. This is best achieved when the hydrophobic surfactant mixes with and/or solubilizes in the active ingredient-acetal mixture to render a liquid or a surfactant which significantly lowers the melting point thereof. Especially advantageous for this use are the hydrophobic ethoxylated nonylphenol surfactants described above, or polyoxyalkylated amines, or carboxylic acids or esters.
Thus, among the surface-active agents referred to above that are chosen in a nonionic emulsion system, in the case of the hydrophilic agents, those which contain at least 7 alkylene oxide units; whereas surface-active agents containing fewer than 7 alkylene oxide units are chosen in the case of lipophilic surface-active agents.
In addition to the O/W, it is advantageous to incorporate an anionic surfactant like sulphonic acids, such as long-chain alkylbenzene sulphonates, optionally in the form of amine or ammonium salts. For example, ammonium dodecylbenzenesulphonate is advantageously employed. With reference to the emulsion compositions described above, between about 0 and 10 g/liter, preferably about 2 to 10 g/liter of the anionic surfactant is employed.